


Vitamin D

by mechahotwings



Category: Undertale (Video Game)
Genre: Bad Puns, Ecto-Genitalia (Undertale), Ecto-Penis (Undertale), Ecto-Tongue (Undertale), F/M, Lactation, Lactation Kink, Plot What Plot/Porn Without Plot, Reader Is Not Frisk, Vaginal Fingering, Vaginal Sex, light humiliation, reader is female
Language: English
Status: Completed
Published: 2018-02-22
Updated: 2018-02-22
Packaged: 2019-03-22 12:04:16
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 1,538
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/13763778
Author URL: https://archiveofourown.org/users/mechahotwings/pseuds/mechahotwings
Summary: Sans needs vitamin d for strong, healthy bones.You are more than happy to give it to him.





	Vitamin D

**Author's Note:**

> I'm not sorry.

The armchair creaked as you settled down into the cushion. You pulled the lever along the side to put your feet up and recline your seat. After a long day of work, you wanted nothing more than to kick back and relax, but you had to work on something else. Maybe work was too strong of a word. It’s not like you were standing for hours and hours like your real job. You put Netflix on the television, bringing up some animal documentary narrated by David Attenborough that you could zone out to.

Then you lifted up your shirt and pushed up your bra, exposing your chest. Your tits felt swollen and heavy. With gentle hands, you began to massage your breasts. Tiny beads of milk began to pop up from your sensitive nipples. You let out a deep breath, sinking further into the armchair.

You couldn’t believe you let Sans talk you into this shit.

It had been a lengthy process of taking herbal supplements, stimulating your nipples, and pumping, but you had finally began producing milk; no baby required. Over that time, your boobs grew bigger. You had to keep special pads in your bra to stop any leaks. And you had to pump. Every. Single. Day.

At least Sans made up for your inconvenience in the bedroom.

With practiced hands, you lifted the pumps up to your chest and attached them to your nipples so that they suctioned in place. The breast pumps worked in tandem, releasing spurts of milk from your sensitive breasts and collecting them into the bottle. You sighed in relief as you felt your load lighten.

You could hear the door open and close and the familiar shuffle of Sans’ feet against the carpet as he came into the living room. The white pinpricks in his sockets brightened as he watched the milking. He couldn’t suckle himself; he had no lips to latch on with, or cheeks, or lungs-- none of the necessary equipment, really. But he was always content to watch and to drink the end product. Somehow. You didn't really understand how a skeleton could drink.

He grinned at you. There was a pun coming, and you knew it.

“Don’t you dare.” You narrowed your eyes.

“are you in a bad _moo_ d, babe? there’s no need to s _cow_ l.”

You groaned as he climbed into the chair with you, straddling your hips. For someone made completely of bones, he was surprisingly weighty. Sans removed one of the cups from your chest. His bony hands groped at your tits, kneading them and forcing a cascade of milk out of your nipples. On your exposed breast, the milk dribbled down your chest in a thin, white stream. Sans opened his jaws, a blue light coalescing inside his mouth. A blue tongue lolled out, and he lowered his head to lap up the milk he had released. It was warm, wet, and sticky. It slid along your skin in long, languid licks.

His hands continued to massage your boobs, releasing more and more milk. He licked in circles around your sensitive nipples, greedily pulling in every last drop like a man dying of thirst. You groaned and held the back of his skull with one hand, pressing his mouth to your heated skin.

“Why are you doing this again?” You asked breathlessly, clenching your thighs together in an attempt to relieve the growing pressure and warmth in your core. It didn’t help.

“because milk is good for bones.” He replied, his teeth grazing against your dusky areola. “and i think this is as much of a _teat_ for you as it is for me.”

Sans wasn’t wrong. You had liked him playing with your nipples before, and now they were hyper-sensitive with your new milk production. He tugged on the hard bud, squirting a jet of milk into his waiting mouth.

“God, you're so depraved.” You muttered, one of your hands already roving south.

“i’m just trying to get some vitamin d.” Sans chuckled, massaging your tits as you hiked up your skirt and slid your fingers underneath your panties.

“I better get some D in a minute.” Your folds were already slick with arousal. As you delved between the wet lips, you sighed as the pad of your finger dragged across your clit. With a steady rhythm, you rubbed and rolled your clit with your fingers as Sans’ weight pressed down onto you. He reattached the pump to your chest and pulled the lever on the side of the chair. The leg rest came down and the two of you rocked forwards. In this new position, you couldn't touch yourself as well, so you stopped.

“you know the drill, babe.” Sans said, patting your cheek and getting up.

Holding the filling bottle with one hand, you stood up and settled onto the floor. You got onto your hands and knees and your breasts continued to be milked by the pump as they hung down like obscene udders. Sans pushed up your skirt and pulled your damp underwear down to the middle of your thighs. Magic coated his finger bones, making them look like blue sausages. He slapped your ass with one bony hand as the other slid across your dripping sex. The new fingers felt a lot like silicone.

He eagerly pressed a finger into your cunt and it slipped in easily. The finger curled inside of you so the tip could rub at your g-spot. You bucked your hips back against his hand, his finger sliding in deeper.

“is my little dairy cow all pent up?” Sans teased, adding a second finger into your entrance. It stretched you pleasantly.

“Don't call me that.” You growled, feeling your cheeks heat up.

“i think i mis _herd_.” Sans drawled. “what does the good little cow say when she wants to get _fucked_?” He punctuated the word with a quick thrust of his arm, pushing into you up until his last knuckle.

“M-moo.” Your cheeks burned. Molten blood coursed through your veins.

“what was that?” His two fingers scissored within your depths.

“MOO.” You arched your back. Sans was laughing as he finger fucked you at an easy pace.

“that wasn't so hard, was it?” He cooed.

You wanted to say “fuck you,” but you had to be good if you wanted him to satisfy you. His fingers pulled out of you, and you heard him pulling down his shorts. There was a moment's pause as he conjured up a cock onto his pelvis. When he was ready, he lined it up with your hole and pushed forwards.

A breathy sigh forced its way out of your lungs as you were completely impaled on his turgid cock. He grunted as his pelvic bones pushed into your ass. Sans rocked his hips slowly, letting you adjust to his length. Just when you were getting into the rhythm of things, he stopped.

You let out a sound of frustration, punctuated by the sucking of the breast milker.

“one more time: what does the dairy cow say when she wants to get fucked?”

“MOO--” Your shout turned into a high keening sound when he started fucking you hard and fast.

His bony hands gripped the globes of your ass, squeezing with every ardent pump of his hips. His strokes were deep, the length of the shaft filling you completely. Your tits swayed and bounced with the force of the pounding, but the pump stayed latched on.

You bucked your hips in time with him. The ridges along the cock were rubbing against nerves that sent sparks of pleasure along your body. His pendulous balls, filled with cum, slapped loudly against you.

If he could see your face; if he could see your mouth open in pleasure, eyes practically rolling back into your head, you'd never hear the end of it. You were panting and he continued to fuck you, slamming into your wet cunt with ease.

The heat and pressure was mounting in you, and you came. A cry escaped you as Sans continued to piston into you, drawing out every last bit of orgasm as you spasmed and writhed on his thick, ribbed cock. He came with a grunt and slowed his merciless pace. You felt his seed flood you in hot spurts that filled you up. Cum leaked out of you, trickling down your spread thighs.

Sans paused for a moment, then slowly withdrew his length, dragging out every ridge until you were weak in the knees. Legs trembling, you remained on all fours as Sans pulled up his shorts and shuffled around to the front of you. He picked up the still sucking breast pump and turned it off then pulled the cups off your chest. You sighed in relief when your breasts were freed.

Sans detached the bottle from the end of the tube and poured your milk straight into his open jaws. Heat flushed your cheeks as he drank in front of you. He finished and turned to you, some milk clinging to his teeth. “get cleaned up, babe. we've gotta get a _moo_ ve on if you want to meet up with the others at Grillby's."

You groaned.

**Author's Note:**

> Kudos, bookmarks, and comments are always appreciated. I'm open to constructive criticism, so tell me why this sucked.


End file.
